Circuit controlling system



Jum 27, 1939. E, w SEEGER Em 2,164,os7

cmcunr' coNTRoLLING SYSTEM Filed Sept. 4, 1957 mw m mvmkm iww c. 5%

with resulting damage Patented June 27, 1939 UNITED sTTEs OIRCUIT CONTROLLING SYSTEMA Edwin W. Seeger and Glendon C. Brown, Wau- PATENT oFFlcE V REISSUED watosa, Wis., assignors to Outlet-Hammer, Inc.,

Milwaukee, Wis., a' corporation Application September 4, 1937, Serial No. 162,544

(cl. ma szo) 10 Claimsy.

The present invention relates to circuit controlling systems, and more particularly to systems requiring provision for time elements.

Where electronic apparatus such as an X-ray tube having a heated c'athode is to be energized to conduct current for a given period it is important that the heated cathode be at a substantially normal temperature before the main discharge circuit is energized in order to avoid injury to the cathode. Also it is often necessary to time the period of energization of the X-ray tube very accurately to prevent over-exposure to the exposed object, and it is desirable that after an exposure period the circuit be rendered inactive pending manual operation of a. pilot switch.

An object of the present invention is to provide a simple and effective system affording the desired control of such X-ray tubes and other devices.

Another object is to provide a system aifording graduation of the power supplied to the X-ray tube or other transiating device; and to afford a time limit to supply of power at one value and also time limit to supply of power at another value.

Another object is to provide a system which aiiords such time limit with accuracy and which if desired may be designed to insure against re'- peated cycles of operation except upon manual operation of a pilot switch.

Other objects and advantages will hereinafter appear.

The accompanying drawing illustrates diagrammatically one embodiment of the inventiori which Will now be described, it being understood that the embodirnent illustrated is susceptible of modification without departing from the scope of the appended claims.

Referring to the drawing, there is shown an X-ray tube i to be supplied with energy from lines L1 and L2 supplied 'with alternating current. The tube i which has a heated cathode 2 has its main electrodes connected across secondary winding 3 of a -transformer 4 which has a primary winding and another secondary Winding 6.' The secondary winding 6 is connected to the terminais of the cathode 2 and Supplies the heating energy for said cathode.

A relay 'l has an energizing winding Scennectedv in series with a resistance 9 across the line L1 L2. This relay has normallydisengaged contacts ll) preferably paralleled by high impedance or indicating lamp II. The contacts l control a circuit for the primary winding of transof Delaware former 4 which circuit includes an impedance I 2 with which is associated a secondary winding 13.

. The winding l3 is connected to a bimetallic strip I 4. and' said winding when energized supplies to said strip heating current. M has associated therewith contacts l5, IS and Il and constitutes a timing switch. The contact 15 normally engages contact IG and disengages said contact 16 when the strip is heated. Fur- The bimetallic strip ther movement of contact I 5 effects its engagement with the normally disengaged contact H. The contact Il is connectedto line L1 While contact I6 is connected to a point between the winding 8 of relay 1 and resistance 9, said contact 16 being also connected to contact 5 through a tact 95 and the terminal of winding E9 which is e Contact 20 is conconnected to contact l. nected to line L1 and contact 2I is connected to a point between impedance l2 and the contacts IO of relay ll.

The primary winding 5 of transformer 4 has The winding |9 20 one terminal connected through contacts 10 of relay 'i to and through impedance l2 to line L1 while theother terminal of winding 5 is connected to line Iii, lines L1 and L2 being connected to a suitable source through a manual pilot switch 23.

With the switch 23 closed and the time switch in normal position current flows from line L1 by conductor 25 through the winding 8 of relay 7 by conductcrs 26 and 21 through resistance 9 to line La. engages its contacts IO to complete a circuit from line L1 through impedance I2 to and through the primary winding 5 of transformer 4 to line L2. The transformer 4 is thus energized at a reduced The relay l is thus energized and 40 voltage so that the potential impressed on the '45 tube i is not sufdcient to produce discharge. However, the secondary Winding 6 is excited to supply sumcient heating current to the cathode 2 to bring it to the proper temperature 'Within a short period. A

The winding 12 being now energized induces a current in winding l3 which heats up the bim'etallic strip I 4 and after lapse of a given time according to the design and adjustment of the time switch the contact S5 disengages contact 16 and engages contact I'l. When the contact I5 from line I..1 by conductors 25 and 29 to contact 20 and bridging contact 22 by conductor 30 to and through winding IS 'to line L.

When the impedance I2 is short-circuited the bimetallic strip H is permitted'to cool and'after lapse of a given time the contact IS disengages contact I'I and shortly thereafter reengages contact IG. Reengagement of contact I5 with contact I6 short-circuits the winding 8 of relay 'I causing said relay to release to insert impedance II in series with the transformar winding 5 for stopping discharge of the tube I. The shortcircuit for the winding -to discharge again the pilot switch 23 must be opened to deenergize relay I8. When the relay I8 opens it interrupts the short-circuit of the winding 8 of relay 1 whereupon'thesystem is prepared for a further cycle of operation upon Vreclosure of switch 23.

The impedance ll is of a high value, its purpose being to prevent discharg'e of tube I and high voltage transient impulses in the transformer 4 if the contact II! upon deenergization of relay 1 should vibrate and intermittently open -and close the circuit.

The periods of operation may be adjusted in various ways, as 'for instance by relative vadjustment of the contacts I5, IG and Il or by adjustment of the winding I3.

What we claim as new and Letters Patent is:

l. The combination with a translating device and a source of energy therefor, of an impedance, electroresponsive switches to establish energy supply connections for said translating device inclusive and exclusive of said impedance, and control means for said switches comprlsing a thermal switch associated with said ilmpedance to be thermally influenced by the current traversing said impedance, said thermal means controlling the time at which said impedance is excluded and determinlng the duration of the periods in which said switches effect supply of energy to said translating device with said impedance included and with said impedance excluded.

2. The combination. with a translating device and a source of energy therefor, of an impedance, electroresponsive switches to establish energy supply connections for said translating device and to include and exclude said impedance for graduation of the supply of said energy to said translating device, and control means for such switches comprising a manual pilot switch and tiiming means eflective upon actuation of desire to secure by 8 of relay 'I extends fromline L1 by conductors 25 and 29 through the said pilot switch, said timing means determinlng the time of exclusion of said impedance and determining the periods during which said switches efiect supply of energy to said translating device with said impedance included and with said impedance excluded, and said control means insuring against repetition of cycles except upon operation 'of said manual switch for each cycle.

3. The combination with a translating device and a source of energytherefor, of an impedance, electroresponsive switches to establish energy supply connections for said translating device and to include and exclude said impedance for graduation of the supply of energy to said translating device and control means for said switches comprising a manual pilot switch and a therimal switch associated with said impedance to be thermally influenced by the current traversing said impedance, said thermal switch determining the time of exclusion of said impedance and determining the periods during which said switches effect supply of energy to said translating device with said impedance included and with said impedance excluded, and said control means insuring against repetition of cycles except upon operation of said manual switch for each cycle.

4. The combination with a source of energy and a translating device to be supplied thereby, of an impedance, an electroresponsive switch to afford a connection for said translating device to said source through said impedance, a second electroresponsive switch to short circuit said impedance, and control means for said switches including a thermal switch associated with said impedance and thermally responsive to current in said impedance, said means in a given position of said thermal switch effecting response of said 'first mentioned switch and said thermal switch thereafter, but subject to a predetermined delay, eifecting response of said second mentioned switch and after a further predetermined delay eifecting deenergization of said. first mentioned switch.

5. The combination with a source of energy and a translating device to be supplied thereby, of an impedance, an electroresponsive switch to aiford a connection for said translating device to said source through said impedance, a second electroresponsive switch to short circuit said impedance, and control means for said switches including a thermal switch associated with said impedance and thermally responsive to current in said impedance, said means in a given position of said thermal switch eifecting response ,of the first mentioned switch and said thermal switch thereafter, but subject to a predetermined delay,

efiectlng response of said second switch and after closing one circuit gap and normallyopening another circuit gap, an electroresponsive switch to establish a supply connection between' said source of energy and said translating device through said impedance and a second electroresponsive switch responsive to short-circuit said impedance and having its energizing winding connected in a circuit which includes the contacts of 75 Vnect said translating said thermal switch which normally open the circuit gap and connections completed by said second electroresponsive switch when energized and by the contacts of saidv thermal switch which normally close the circuit gap to short-circuit the flrst mentioned electroresponsive switch.

7. The combination with a translating device and a source of energy therefor, of an impedance, a thermally responsive switch responsive to the current in said impedance, said switch having a plurality of contacts certain of which are normally engaged and certain of which are normallyl disengaged, being engageable after` disengagement of the flrst mentioned contact, an electroresponsive switch controllable at will to condevice to said source of energy through said impedance, a second electroresponsive switch responsive to short-circuit said impedance, said second electroresponsive switch having an energizng circuit to be closed upon engagement of the normally disengaged contacts of said timing switch and having a maintaining circuit independent of said thermal switch, and a short-circuit for the operating winding of the flrst mentioned electroresponsive switch controlled jointly by the normally engaged contacts of said thermal switch and contacts of said second electroresponsive switch. t

8. The combination with a translating device' and a source ofenergy therefor, of a transformer having a primary winding and a secondary winding, a thermally responsive switch connected to said secondary winding to be thermally responsive to the current therein, said thermal switch having a movable contact element and cooperating contacts to be engaged thereby selectively, said element normally engaging one of said contacts, an electroresponsive switch responsive to establish a connection between said translating device and said source including said transformer primary winding, a second electroresponsive switch responsive to short-circuit said transformer primary winding and energizable by engagement of the normally disengaged contacts of said thermal switch and having a maintaining circuit independent of said thermal switch and a short-circuit for the energizing winding' of the flrst mentioned electroresponsive switch conmentioned transformer and said source through the primary winding of the second transformer, a

thermal switch supplied with heating current by the secondary winding of the second mentioned transformer, an electroresponsive switch controlled by said thermal switch to short-circuit the primary winding of the second mentioned transformer following response of the first mentioned.

switch but subject to a predetermined delay, and a short-circuit for the operating winding of said first mentioned switch controlled jointly by said second electroresponsive switch and said thermal switch for deenergizing thevflrst'mentioned switch followingresponse of said second electroresponsive switch but subject to a predetermined delay. V

10. The combination with a transformer and a source of energy therefor, a second transformer, an electroresponsive switch to complete a connection between the primary winding of the flrst mentioned transformer and said source through the primary winding of the second transformer, a thermal switch supplied with heating current by the secondary winding of the second mentioned transformer, an electroresponsive 'switch controlled by said thermal switch to short-circuit the primary winding of the second mentioned transformer following response of the flrst mentioned switch but subject to a predetermined delay and a short-circuit for the operating winding of said flrst mentioned switch controlled jointly by said second electroresponsive switch and said thermal switch for deenergizing the first mentioned switch following response of said second electroresponsive switch but subject to a predetermined delay, and a maintaining circuit for said second electroresponsive switch independent of said thermalswitch.

EDWIN W. SEEGER. GLENDON C.'BROWN. 

